Many companies that we talk to about using lean principles ask why it is so important to understand the current state well before moving on. They ask, “Can’t I just envision what I want the future state to look like?” The answer is no. Envisioning the future state of a product family is an activity that will lead to more ‘drive-by’ kaizen that will likely have no direct effect to the bottom line or to business objectives.
It is no secret that I named our company after this amazing Lean tool over 10 years ago. Why am I so enamored with this Lean tool? Well, that’s the purpose of this story.
Back in the late 1990’s when Jim Womack had written Lean Thinking and began talking about mapping out processes to see the value flow (or not flow!), many weren’t sure how. You see, every continuous improvement method I had learned up to that point always included mapping out processes in some way in order to “find the truth”, but none that I had used seemed to make sense to use in the way Jim described. It was then that I dug deeper and found a few examples and descriptions of this mapping technique that instead of trying to map out everything in its complexity and detail, simplified things down to material and information flow. In other words, it focused in on how the customer focused work occurred to the product or service. By this time, Jim Womack and his team at the Lean Enterprise Institute had developed the book, Learning to See. I purchased this book and the World for me forever changed.
Value stream mapping has two parts to the activity of mapping and it starts with mapping out the ‘current state’ and then once the current state is understood, a ‘future state’ map is created to show how value could flow. It is this future state map that becomes the ‘blueprint’ for action and Kaizen activity for improvement.
The Current State
Many companies that we talk to about using lean principles ask why it is so important to understand the current state well before moving on. They ask, “Can’t I just envision what I want the future state to look like?” The answer is no. Envisioning the future state of a product family is an activity that will lead to more ‘drive-by’ kaizen that will likely have no direct effect to the bottom line or to business objectives. Another drawback to skipping the current state step is that it can be difficult to rally the resources you may need if decision makers cannot see the connection to the current reality and how it translates into the future. Creating a good current state map is a critical step to being able to develop the future state of a process.
The current state begins with an analysis of product families to group products that follow similar process steps. By grouping products this way we get a true picture of the product families produced. Remember, the true product families are not necessarily what you would consider product families by output, shape, size, style, or catalogue grouping. Once this step is complete, one product family is chosen to create a current state map for it. The others will be completed one by one as required. There is no sense to waiting until the entire factory is mapped before proceeding to future state and there is also no need to wait. Improvements can be made sooner doing one by one.
At this point all of the processing steps for the product family are identified and lined up in order on our map. For each of these process steps, pertinent data is collected that will help to determine the ability of each process to flow into another. The most common data collected on each process is; cycle time, process time, changeover time, uptime, and number of operators. Other data that may be useful is; process yield, scrap, distance to next operation, work time available, and number of shifts. To complete the map, all of the information flow is also shown. This starts with the customer providing a forecast or an order. It shows how that information is passed on to suppliers as forecasts and orders of raw materials, and finally it shows how the information flows down to the shop floor as the production schedule.
The importance of having this map complete and accurate is demonstrated in the process of developing a future state map. Without a complete picture of the current state, future state can only be developed by wishful thinking.
The Future State
Many companies struggle with the task of developing a future state because they believe that they need some “desire” for what the preferred state of the factory, the machine processes, and the people should be. This is all wrong when it comes to Value Stream Mapping. Envisioning the preferred future is an activity reserved for the purpose of developing Mission and Vision statements for companies while the future state of our processes come from understanding our processes. The future state maps come from the ability to answer nine basic questions about the door-to-door process for a product family. The answers are derived directly from the current state map that has been drawn in order to understand how the process operates today.
The ideas for future state begin by drawing right on our current state maps. Remember to use pencil because you’ll likely need to erase once in awhile! When you are ready to develop your future state map, begin by asking the following questions. (Subsequent articles will help explain some of these terms).
While studying the current state map ask:
- Which processes are Value Added, and which are currently necessary due to the limitations of our current processes? Are there any we can get rid of completely?
- What is our takt time for this product family?
- Will we build directly to shipping or to a finished goods supermarket?
- Where can we create true one at a time flow? The operation balance chart is a wonderful tool to help answer this question.
- Where do we have to set up a type of pull system? When flow is not possible due to shared resources, machine size, machine location, etc., a pull system must be created to eliminate the tendency to push inventory through the system.
- At what single point in the process will we trigger production? This eliminates the need for schedules at every operation and helps pull product through the factory based on real customer need.
- How will we mix the production at the pacemaker process? This is sometimes necessary in order to provide more part numbers each day or each ship window.
- What increment of work will we release to the pacemaker process in order to create a better management timeframe?
- What process improvements are necessary to make the above answers into reality?
The toughest part of this step is to leave the shop floor behind. That is to say, forget about all the stuff you get sucked into each day in order to make product and look purely at the data from the current state map. Once you can do this, you become able to ask the questions of the data and answer objectively. Look at it from the standpoint of observing someone else’s factory where you may have no intricate understanding of the individual processes and their nuances. Just look at the process steps and the data on the current state map for the product family you’re studying.
If you have feedback about this article or would like more information about value stream mapping or our workshops, please email info.com.